Intravenous (IV) additives and injectable unit dose programs are administered in many hospitals as one method for introducing medications into a patient for a prescribed treatment. In prescribing an IV additive or an intramuscular medication unit dose treatment program, the doctor may order any one of a number of drugs or vitamins to be injected intramuscularly or added to the solution in a sterilized IV container and administered intravenously to a patient. The quantity of the drug or vitamin is also prescribed by the doctor to adjust the dosage of medication to the intravenous solution to the needs of each patient. In addition to the method of adding drugs and vitamins to an IV container for an IV additive program, some IV additive programs may be instituted by combining an IV additive solution in a "piggyback" arrangement of containers for certain specialized treatments requiring a combination of drugs.
In a hospital's IV additive program, the prescribed medication is added to an IV bottle or plastic IV bag by inserting a needle into the "target area" of a membrane closing the top of an IV solution bottle or a membrane covering the inlet port of a plastic IV bag. The IV solution bottle has a sterile seal covering the membrane area prior to the time of adding medication to the bottle. The IV bottle must be resealed under sterilized conditions to prevent airborne bacteria, such as Pseudomonas Aeruginosa, from accumulating on the exposed surface of the IV bottle covering. In addition to maintaining a sterile surface of a bottle, the resealing of the bottle alerts the hospital staff that the original contents have been altered by the pharmacy and have not been altered since then. A hospital's nursing staff is trained not to adminster the IV solution unless one of the members of the staff mixed the contents, or there is some means to alert the nursing staff that the contents have not been altered since they were prepared in the pharmacy department. In the case of the plastic IV bag, the sealing cover protects the "plug" in the inlet port from becoming dislodged during storage or transport, and the cover also alerts the pharmacy that the contents have not been altered so that the container and its contents may be reissued to another patient.
The prior practice has been to utilize a plastic cap for resealing the IV containers. The plastic cap for the bottle container snaps over the top of the metal rim surrounding the rubber membrane to completely cover and seal the top of the solution bottle. For the IV bags, the prior practice uses a plastic cap or a heat shrink plastic wrap to reseal the plastic IV bag's inlet port. The seal for the IV bag is seldom removed, since a separate outlet is used for administering the drugs to the patient. However, in those instances when it is necessary to remove the inlet port seal, the plastic cap sometimes must be fractured. In removing the plastic cap, the rubber plug in the inlet port may be dislodged, breaking the sterility barrier and requiring a hospital to discard the IV bag.
In an effort to hold down hospital costs in reducing the allocation for expensive inventory space, the prior practice of most hospitals has attempted to maintain only one size plastic cap in inventory for IV bottles and another one for IV bags. Since the IV solution and the piggyback containers are manufactured by different manufacturers, the tops are not of uniform diameter. The plastic caps do not provide the necessary sterilized seal in resealing the IV containers if there is not a tight mechanical closure over the container top. As a result of the tight fit required between the plastic cap and a metal seal of a bottle, the nursing staff often faces a problem in attempting to separate the plastic cap from the metal rim. The nursing staff often must resort to using expensive surgical instruments or scissors, which can be damaged, to help them in prying off the plastic sealing cap. The difficulty of removing the plastic caps from IV containers has resulted in some hospitals issuing pliers to the nursing staff to remove the caps. Removal of plastic caps or resealing intravenous containers has resulted in the inefficient use of the services of skilled personnel, such as registered nurses, in attempting to remove container closures. More importantly, many of the prior art closures and methods for sealing IV solution bottles do not allow a nurse inspecting a container without a sealing cover to know where it was removed, if another drug was added, if it was previously resealed, or how the drugs were added. In such a situation, rather than risk exposing the patient to a serious infection from harmful bacteria which may have accumulated on top of such a container, or the risk from any tampering with the container, the nurse must often reject the container, which results in wasting the medication as well as a delay in administering the medication to a patient while additional medication is reordered from the pharmacy department.
The present hospital practice does not normally include removing the plastic cap or heat shrink plastic wrap applied to the inlet port of an IV bag. Unlike the IV bottle, a separate outlet port is provided for connecting the container intravenously to the patient. The reentry into the inlet port that has become contaminated pushes contamination back into the bag. However, the difficulties encountered in reentering the inlet port with prior resealing techniques often result in the loss of the entire container and its contents on those occasions when it is either desirable to change the dosage of the medication or the unit is not used and is returned to the pharmacy department. As the medication in the container may be quite expensive, this represents a substantial loss to the hospitals.
On May 12, 1981, U.S. Pat. No. 4,266,687 issued to the same assignee as the present invention. This patent is for a sealing cover and method for resealing an intravenous container. The invention covered by that patent is an improvement over the prior practice of resealing IV bottles with molded plastic caps.
On June 28, 1983, U.S. Pat. No. 4,390,104 issued to the same assignee as the present invention and is for a flexible plastic sterile closure system for containers. The invention covered by that patent provides further improvements, including the use of a sealing cover with a layer of material having "t-shaped" slits to promote separation of the cover to leave telltale strips of material on the port to indicate use.
On Jan. 3, 1984, U.S. Pat. No. 4,423,819 issued to the same assignee as the present invention and is for a flexible sterile closure system for containers. The inventions covered by that patent are additional improvements, including the improvement in the flexibility of the cover seal to better form and adhere the cover seal to a container.
While the sealing covers and methods for resealing an intravenous container in these patents have proved extremely effective in use, specific intravenous container designs require the use of especially adapted sealing covers. One example of a particularly difficult intravenous container to reseal is the intravenous bag which incorporates a side injection port. The side injection port includes a cylindrical portion which extends outward from the side of the intravenous bag. An injectable membrane covers the exposed end of the cylindrical portion and has an outer surface of convex shape. A needle can be inserted through the injectable membrane in order to fill or empty the bag. A need exists for a flexible cover having the advantages of the covers in the aforementioned U.S. patents, but that is specifically adapted for use with an intravenous bag having a side injection port.